Investments (Details) - USD ($) $ in Thousands	3 Months Ended
Aug. 31, 2021	Aug. 31, 2020	May 31, 2021
Investments, Debt and Equity Securities [Abstract]
Cash surrender value of insurance policies	$ 274,721		$ 252,061
Equity method investments	18,383		19,388
Cost method investments	2,164		3,167
Total investments	295,268		$ 274,616
Losses due to impairment	$ 0	$ 0

Carrying amount as of the balance sheet date of amounts which could be received based on the terms of the insurance contract upon surrendering life policies owned by the entity.

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This item represents the carrying amount on the entity's balance sheet of its investment in common stock of an equity method investee. This is not an indicator of the fair value of the investment, rather it is the initial cost adjusted for the entity's share of earnings and losses of the investee, adjusted for any distributions (dividends) and other than temporary impairment (OTTI) losses recognized.

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The amount by which the fair value of an investment is less than the amortized cost basis or carrying amount of that investment at the balance sheet date and the decline in fair value is deemed to be other than temporary, before considering whether or not such amount is recognized in earnings or other comprehensive income.

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Sum of the carrying amounts as of the balance sheet date of all investments.

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Amount of investments classified as other.

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